Fractional flow reserve (FFR) is a technique for measuring differences in pressure across an arterial stenosis, with the measurement itself being useful to determine the severity of the stenosis. The guidelines for stenotic lesion treatment using FFR have been established based on dimension of a 0.014″ outer-diameter pressure wire. It has been shown that this dimension does not significantly affect FFR measurement in the critical range of 0.75-0.8.
By way of example, a patient's luminal organ (such as an artery, for example), may have a 2 mm inner diameter at a location without a lesion, and a 1 mm in diameter at the lesion site. A 0.014″ (0.356 mm) diameter wire is approximately half of the diameter of an inner diameter of a vessel at a lesion location if the inner diameter is 1 mm. Advancing a catheter over the pressure wire, such as a 0.02″ outer diameter catheter), adds nearly 50% in size to the overall device, which has severe implications with respect to obtaining an accurate FFR measurement.
In view of the foregoing, methods for determining accurate FFR measurements in the view of catheters having dimensions larger than established guideline devices, and devices and systems for facilitating the same, would be appreciated in the marketplace.